| 摘要 |
PURPOSE:To equalize the gate cut-off voltage by a method wherein an N+ conductive layer at high concentration to be source and drain part near a gate electrode is selfmatchingly formed with high precision and excellent reproducibility without diffusing a gate metal in an operating layer. CONSTITUTION:An Si<+> ion is implanted in a high resistance GaAs substrate 4 to form an N type operating layer 5. Then a silicon oxide film 21 is grown and a plasma silicon nitride film 22 is further grown to form patterns 21, 22 to be gate parts by etching process. Firstly the oxide film 21 is side-etched and Si<+> ion is implanted to form a high concentration conductive layer 6. Secondly overall surface is covered with a plasma nitride film 23 and after coating and drying up a photoresist film 24, overall surface is etched to expose the pattern 21 and the film 24 is removed to form electrodes 1-3. In such a constitution, gate metal may be prevented from diffusing in the operating layer as well as the gate Schottky characteristics from deteriorating to equalize the gate cut-off voltage. |
